I. Field of the Invention
The present invention relates to a rotational laser apparatus having reciprocating laser scanning systems, and in particular relates to ones which are rotating laser apparatus used for marking, which project a laser beam onto an object and which include the reciprocating laser scanning system.
II. Description of the Prior Art
Conventionally, a rotative irradiation type laser apparatus is disclosed in Japanese Patent Application Laid Opens No. SHO-62-95419 (1987) and No. SHO-63-179208 (1988). These apparatuses use He-Ne gas lasers or laser diodes or the like as a laser source.
The conventional rotative irradiation type laser apparatus using He-Ne gas laser has had a problem that, when a distance between the apparatus body and an object is great, marking with a high efficiency becomes difficult because the He-Ne gas laser arriving at the object is attenuated in energy is hardly visible.
In addition, the rotative irradiation type laser apparatus using laser diodes projects an infrared laser beam, which requires the location of an infrared light sensor on the object.
In the recent years, a laser diode capable of emitting a visual wavelength laser whose wavelength approximates that of the He-Ne gas laser has been proposed. However, the problem still remains wherein, when the distance between the apparatus body and an object is great, a marking operation with a high efficiency is difficult because the energy of laser beam arriving at the object is attenuated and hardly visible.